1. Field of the Invention
The present invention relates to housings for compressors such as centrifugal compressors or mixed flow compressors used in aviation gas turbines, marine superchargers, and automotive superchargers, for example.
2. Description of Related Art
A known compressor used for aviation gas turbines, marine superchargers, and automotive superchargers uses the technology disclosed in Japanese Unexamined Patent Application, Publication No. 2008-19798.
In recent years, attempts have been made to construct the entire compressor housing of plastic from the standpoint of reducing the weight and cost. However, as indicated by double-dashed chain lines in FIG. 6, an outlet part (more specifically, a part where a volute 101 is provided) of a housing 102 is thermally deformed by air having a high temperature (for example, 180° C.) compressed in a compressor 100, thus increasing a clearance between blade tips 7a of blades 7 and an inner circumferential face 102a of the housing 102, thereby reducing the efficiency of the compressor 100.
Thus, a housing 202 of a compressor 200 shown in FIG. 7 has been conceived; the entire wall of the housing 202 is made thick toward the outer side in the radial direction, and ribs 203 are provided on the outer surface of the housing 202 where the volute 101 is formed. However, in the housing 202 of the compressor 200, the length in the radial direction is increased, thus causing an increase in the size and the weight of the entire compressor 200.
Note that the solid line drawn in the center portion of the housing 202 in FIG. 7 indicates the wall thickness of the housing 102 shown in FIG. 6.